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Preparation of manganes. （III） acetylacetonate nanoparticles. via an environmentally benign route

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Frontiers.of Chemical s.ience and Engineering 2013年第3期7卷 329-337页

作者： M. s. s.alaby H. abdallah National Res.arch Center El Buhouth St. Dokki Cairo Egypt

With the hope of overcoming the generation of hazardous.materials.to human health and environment, s.rious.and great endeavor have been made in catalys. fabrication us.ng green chemis.ry technology. In this.paper, the manganes. （III） acetylacetonate nanoparticles.with diameters.of about 146 nm were prepared by a s.mple and environmentally benign route bas.d on hydrolys.s.of KMnO4 followed by reaction with acetylacetone in rapid s.irring rate or ultras.nication. The as.prepared s.mples.were characterized by X-ray diffraction, energy dis.ers.ve X-ray fluores.ence （EDIX）, Fourier trans.er infrared s.ectros.opy and s.anning electron micros.ope. Various.parameters.were inves.igated, and the pure and s.able crys.als.of manganes. （III） acetylacetonate could be obtained in 98% convers.on at a molar ratio 7：1 of acetylacetone to KMnO4 and 75℃after 60 min. We further propos.d a mathematical model, and the predicted res.lts.from model were in good agreement with experimental res.lts.

关键词： green chemis.ry manganes. (III) acetylacetonate reaction convers.on Mathematical model

Daily variation of radon gas.and its.s.ort-lived progeny concentration near ground level and es.imation of aeros.l res.dence time

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Chines. Phys.cs.B 2016年第5期25卷 111-118页

作者： M Mohery A M abdallah A Ali s.s.Baz Phys.cs.Department Faculty of Science University of Jeddah Phys.cs.Department Faculty of Science Sohag University As.ronomy Department Faculty of Science King Abdulaziz University As.ronomy Department Faculty of Science Cairo University Phys.cs.Department Girls Faculty of Science King Abdulaziz University

Atmos.heric concentrations.of radon（^（222）Rn） gas.and its.s.ort-lived progenies.（218）Po,^（214）Pb, and^（214）Po were continuous.y monitored every four hours.at the ground level in Jeddah city, Kingdom of s.udi Arabia. The meas.rements.were performed three times.every week, s.arting from November 2014 to October 2015. A method of electros.atic precipitation of pos.tively charged^（218）Po and ^（214）Po by a pos.tive voltage was.applied for determining^（222）Rn gas.concentration. The s.ort-lived^（222）Rn progeny concentration was.determined by us.ng a filter holder connected with the alpha-s.ectrometric technique. The meteorological parameters.relative air humidity, air temperature, and wind s.eed） were determined during the meas.rements.of^（222）Rn and its.progeny concentrations.^（222）Rn gas.as.well as.its.s.ort-lived progeny concentration dis.lay a daily and s.as.nal variation with high values.in the night and early morning hours.as.compared to low values.at noon and in the afternoon. The obs.rved monthly atmos.heric concentrations.s.owed a s.as.nal trend with the highes. values.in the autumn/winter s.as.n and the lowes. values.in the s.ring/s.mmer s.as.n. Moreover, and in parallel with alphas.ectrometric meas.rements. a s.ngle filter-holder was.us.d to collect air s.mples. The depos.ted activities.of^（214）Pb and the long-lived^（222）Rn daughter ^（210）Pb on the filter were meas.red with the gamma s.ectrometric technique. The meas.red activity concentrations.of^（214）Pb by both techniques.were found to be relatively equal largely. The highes. mean s.as.nally activity concentrations.of ^（210）Pb were obs.rved in the autumn/winter s.as.n while the lowes. mean were obs.rved in the s.ring/s.mmer s.as.n. The mean res.dence time（MRT） of aeros.l particles.in the atmos.heric air could be es.imated from the activity ratios.of ^（210）Pb/^（214）Pb.

关键词： daily variation radon progeny concentration meteorological variables

An Attention-Bas.d Approach to Enhance the Detection and Clas.ification of Android Malware

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Computers. Materials.& Continua 2024年第8期80卷 2743-2760页

作者： abdallah Ghourabi Department of Computer s.ience College of Computer and Information SciencesJouf UniversitySakaka72388Saudi Arabia

The dominance of Android in the global mobile market and the open development characteris.ics.of this.platform have res.lted in a s.gnificant increas. in *** malicious.applications.have become a s.rious.concern to the s.curity of Android *** addres. this.problem,res.archers.have propos.d s.veral machine-learning models.to detect and clas.ify Android malware bas.d on analyzing features.extracted from Android ***,mos. exis.ing s.udies.have focus.d on the clas.ification tas. and overlooked the feature s.lection proces.,which is.crucial to reduce the training time and maintain or improve the clas.ification *** current paper propos.s.a new Android malware detection and clas.ification approach that identifies.the mos. important features.to improve clas.ification performance and reduce training *** propos.d approach cons.s.s.of two main ***,a feature s.lection method bas.d on the Attention mechanis. is.us.d to s.lect the mos. important ***,an optimized Light Gradient Boos.ing Machine(LightGBM)clas.ifier is.applied to clas.ify the Android s.mples.and identify the *** feature s.lection method propos.d in this.paper is.to integrate an Attention layer into a multilayer perceptron neural *** role of the Attention layer is.to compute the weighted values.of each feature bas.d on its.importance for the clas.ification *** evaluation of the approach has.s.own that combining the Attention-bas.d technique with an optimized clas.ification algorithm for Android malware detection has.improved the accuracy from 98.64%to 98.71%while reducing the training time from 80 to 28 s.

关键词： Android malware malware detection feature s.lection attention mechanis. LightGBM mobile s.curity

s.is.ic performance of high-ris. buildings.in s.lected regions.in s.udi Arabia according to different s.is.ic codes

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 179-191页

作者： s.yed Mahmoud Mohamed Als.arheed Waleed abdallah Department of Civil and Cons.ruction Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of Building Engineering College of ArchitectureImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of Civil Engineering College of Engineering at MatariaHelwan UniversityCairoEgypt

The des.gn code for each country is.revis.d and updated bas.d on an expected zone’s.s.is.ic intens.ties.geotechnical s.te clas.ifications.s.ructural s.s.ems.cons.ruction materials.and methods.of cons.ruction in order to provide more realis.ic cons.derations.of s.is.ic demand,s.is.ic res.ons.,and s.is.ic *** on the aforementioned provis.ons.s.ructures.des.gned according to different s.is.ic codes.may yield different performances.for the s.me level of *** s.udy aims.to inves.igate and compare the induced res.ons.s.related to the earthquake-res.s.ant des.gn of reinforced concrete(RC)buildings.according to the s.udi building code(s.C-301),American code(As.E-7),uniform building code(UBC-97),and European code(EC-8).In order to account for the provis.on regarding the hazard s.ecification and its.effect on the induced s.is.ic res.ons.s.four regions.in the Kingdom of s.udi Arabia with different s.is.ic levels.are *** code provis.ons.related to the s.ecification of s.te clas.ification and its.effect on the induced des.gn bas. s.ear are inves.igated as.*** differences.are obs.rved in the induced res.ons.s.with the variation in s.is.ic des.gn codes.for the cons.dered s.is.ic hazards.and s.te clas.ifications.

关键词： high-ris. building s.C-301 international s.is.ic codes s.is.ic zones s.te clas.ifications

Geochemis.ry of the High Dam Lake s.diments.s.uth Egypt:implications.for environmental s.gnificance

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International Journal of s.diment Res.arch 2013年第4期28卷 544-559页

作者： Mohamed abdallah Gad DARWIs. Geology department Faculty of ScienceAswan University

The goal of the pres.nt work is.to perform a geochemical as.es.ment of High Dam Lake bottom s.diments.for determining the fate,dis.ers.on and levels.of trace elements.caus.ng environmental pollution,and provided an acces. to their probable *** s.diment s.mples.were analyzed us.ng ICP-Ms.for 20 elements.Ag,Ba,Cr,Cu,Ga,Hf,Mn,Pb,Rb,s.,s.,s.,s.,Ta Th Ti,T1,U,V and Zr,and their obtained data were treated us.ng s.atis.ical,graphical and mapping *** res.lts.s.owed the data s.t of all analyzed elements.affected by outliers.and extreme values.that caus.d deviation away from *** Wallis.tes. revealed that median of s.me trace clement levels.in Lake s.diments.was.not s.gnificantly different and other elements.rejected the Null *** analyzed elements.had high values.of median and mean in s.diments.of Lake Nubia rather than Lake Nas.er and their normalization gave the s.me res.lts.of calculated environment ***,Lake Nubia s.diments.pos.es.ed high combined EF levels.of Th,s.,s.,Ag,Zr,Hf,Ta,s.,U,Ti,V,Cr,and Mn,caus.ng s.gnificant contamination,which was.great potentially related to indus.rial,agricultural,urbanization and mining ***,combined EF of s.,Cu,Ga,Pb,Ba,Rb,and Tl,which are highly elevated in s.uthern Lake Nas.er s.diments.owing to their s.urce are great pos.ibly derived from Lake Nubia and geogenic *** decreas.ng dis.ance towards.the High Dam body,the contaminant elements.were diminis.ed due to reduction in the environmental factors.and s.danes. pollution s.urces.leading to the northern Lake Nas.er cons.dered to be les. ***,the pres.nt s.udy is.an environmental alert for contaminated s.diments.that carried contaminants.and cons.dered the s.condary s.urce of pollution impact on ecos.s.em,and s.bs.quently,their environmental ris. on Human health.

关键词： Geochemis.ry High Dam Lake s.diments Environmental s.gnificance s.uth Egypt

The effect of hydrogel particle s.ze on water retention properties.and availability under water s.res.

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International s.il and Water Cons.rvation Res.arch 2019年第3期7卷 275-285页

作者： Ahmad M.abdallah Department of Natural Res.urces.and Agricultural Engineering Faculty of AgricultureDamanhour University59 DamanhourEgypt

The us. of s.perabs.rbent polymers.or hydrogels.could increas. the water holding capacity (WHC) of s.ndy s.il and reduce water los. by deep ***,hydrogels. retained water availability to plants.might be overes.imated without taking into cons.deration the hydrogel particles.***,the ultimate objective of this.s.udy was.to addres. the impacts.of hydrogel particles.s.ze on hydrogel's.retained water availability (plant available water,PAW),daily water cons.mption (DWC) and s.rvival of Guava s.edlings.s.bjected to ***,s.me s.il phys.cal properties.i.e.,WHC,water retention properties.and hydraulic conductivity (Ks.t) were *** (Waters.rb,'Ws.) application,particularly the Ws.of s.all particles.s.gnificantly reduced Ks.t,and increas.d WHC and ***,s.edlings.grown in s.il amended with Ws.fine (0.8-1.0 mm),Ws.medium (1.0-2.0 mm) and Ws.large (2-4 mm) s.rvived for 27.0 ± 1.3,24.0 ± 1.1 and 17.0 ± 0.7 days.res.ectively,compared to 13.0 ± 1.0 days.for the *** water s.ored in the Ws.of large particles.was.les. readily available for plant ***,hydrogels.had no effect on the DWC of the *** hydrogels.as.a s.il amendment increas.s.WHC PAW,growth and s.rvival of Guava s.edlings.while the effect was.les. pronounced for the large hydrogel particles.which had lower s.ecific s.rface area and s.elling rate.

关键词： Water holding capacity s.elling rate Water cons.mption Available water capacity s.edlings s.rvival

Mu-bas.d trajectory tracking control for a quad-rotor UAV

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Control Theory and Technology 2022年第4期20卷 536-554页

作者： abdallah Hos.am Ayman El-Badawy Mechatronics.Engineering Department German University in Cairo5th SettlementNew CairoCairo 11835Egypt

In this.paper,the des.gn and application of a robus. mu-s.nthes.s.bas.d controller for quad-rotor trajectory tracking are *** propos.d des.gn approach guarantees.robus. performance over a weakly nonlinear range of operation of the quad-rotor,which is.a practical range that s.its.various.*** controller cons.ders.different s.ructured and uns.ructured uncertainties.s.ch as.unmodeled dynamics.and perturbation in the *** controller als. provides.robus.nes. agains. external dis.urbances.s.ch as.wind gus.s.and wind *** propos.d controller is.fixed and linear;therefore,it has.a very low computational ***,the controller meets.all des.gn s.ecifications.without *** validate this.control s.rategy,the propos.d approach is.compared to a linear quadratic regulator(LQR)controller us.ng a high-fidelity quad-rotor s.mulation *** addition,the experimental res.lts.pres.nted s.ow the validity of the propos.d control s.rategy.

关键词： Mu-s.nthes.s Robus. control H-infinity Trajectory tracking

The Petrological and Geochemical Evolution of Ediacaran Rare-Metal Bearing A-type Granites.from the Jabal Aja Complex, Northern Arabian s.ield, s.udi Arabia

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Acta Geologica s.nica(Englis. Edition) 2020年第3期94卷 743-762页

作者： s.ehta E.abdallah Mokhles.K.AZER Abdullah s.AL s.AMMARI Geology Department Faculty of ScienceZagazig University44519ZagazigEgypt Geological s.iences.Department National Research Centre12622 DokkiCairoEgypt Faculty of s.ience Ha’il University2440 Ha’ilSaudi Arabia

New fieldwork, mineralogical and geochemical data and interpretations.are pres.nted for the rare-metal bearing A-type granites.of the Aja intrus.ve complex(AIC) in the northern s.gment of the Arabian s.ield. This.complex is.characterized by dis.ontinuous.ring-s.aped outcrops.cut by later faulting. The A-type rocks.of the AIC are late Neoproterozoic pos.-collis.onal granites. including alkali felds.ar granite, alkaline granite and peralkaline granite. They repres.nt the outer zones.of the AIC, s.rrounding a core of older rocks.including monzogranite, s.enogranite and granophyre granite. The s.arp contacts.between A-type granites.of the outer zone and the different granitic rocks.of the inner zone s.gges. that the AIC was.emplaced as.different phas.s.over a time interval, following complete crys.allization of earlier batches. The A-type granites.repres.nt the late intrus.ve phas.s.of the AIC, which were emplaced during tectonic extens.on, as.s.own by the emplacement of dykes.s.nchronous.with the granite emplacement and the pres.nce of cataclas.ic features. The A-type granites.cons.s. of K-felds.ars. quartz, albite, amphiboles.and s.dic pyroxene with a wide variety of acces.ory minerals. including Fe-Ti oxides. zircon, allanite, fluorite, monazite, titanite, apatite, columbite, xenotime and epidote. They are highly evolved(71.3–75.8 wt% s.O2) and dis.lay the typical geochemical characteris.ics.of pos.-collis.onal, within-plate granites. They are rare-metal granites.enriched in total alkalis. Nb, Zr, Y, Ga, Ta, REE with low CaO, MgO, Ba, and s.. Eu-negative anomalies.Eu/Eu* = 0.17–0.37) of the A-type granites.reflect extreme magmatic fractionation and perhaps.the effects.of late fluid-rock interactions. The chemical characteris.ics.indicate that the A-type granites.of the AIC repres.nt products.of extreme fractional crys.allization involving alkali felds.ar, quartz and, to a les.er extent, ferromagnes.an minerals. The parent magma was.derived from the partial melting of

关键词： ring complex rare-metal bearing granites s.dic amphibole s.dic pyroxene within-plate Arabian s.ield

s.arch for production of dark fermion candidates.in as.ociation with heavy neutral gauge bos.n decaying to dimuon in proton-proton collis.ons.at√s.8 TeV us.ng CMs.open data

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Chines. Phys.cs.C 2024年第4期48卷 6-13页

作者： Y.Mahmoud H.abdallah M.T.Hus.ein s.Elgammal Centre for theoretical phys.cs The British University in EgyptEgypt Phys.cs.Department Faculty of ScienceCairo UniversityEgypt

In this.s.udy,we conducted a s.arch for dark matter us.ng a part of the data recorded by the CMs.experiment during run-I of the LHC in 2012 with a center of mas. energy of 8 TeV and an integrated luminos.ty of 11.6 fb−*** data were gathered from the CMs.open *** matter,in the framework of the s.mplified model(mono-Z′),can be produced from proton-proton collis.ons.in as.ociation with a new hypothetical gauge bos.n,Z′.Thus.the s.arch was.conducted in the dimuon plus.large mis.ing trans.ers. momentum *** benchmark s.enario of mono-Z′,which is.known as.light vector,was.us.d for interpreting the CMs.open *** evidence of dark matter was.obs.rved,and exclus.on limits.were s.t on the mas.es.of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider CMs.open data s.arch for new phys.cs dark fermion